US President Barack Obama's administration is dispatching senior intelligence officials and Secretary of State John Kerry to brief members of Congress and staff about the Islamic State militant group in the coming weeks, congressional aides said on Thursday.

Kerry will testify to members of the House of Representatives Foreign Affairs Committee during the week of Sept. 15, an aide said, and

officials from the Office of the Director of National Intelligence and the National Counterterrorism Center will brief congressional staff on Friday, before Congress returns on Monday from its August recess.

Some lawmakers have contended that Obama should seek congressional authorization for airstrikes in Iraq against the Sunni militants. However, it is not clear whether such a vote would take place this month or whether he needs Congress to approve the limited actions already under way.